1. Technical Field
The invention relates to a semiconductor device and a method of manufacturing the same. More specifically, the invention relates to a 3-dimensional semiconductor device and a method of manufacturing the same.
2. Related Art
A nonvolatile memory is a memory device, which maintains stored data although a power supply cuts off. Recently, since improvement of integration of a 2-dimensional memory device, which forms a memory cell on a silicon substrate as a single layer, has reached a limit, a 3-dimensional nonvolatile memory device, which has vertically stacked memory cells on a silicon substrate, has been proposed.
The 3-dimensional memory device includes alternately stacked interlayer insulating layers and word lines, and channel layers, which pass therethrough, and memory cells are stacked along the channel layers. Also, contact plugs are connected to the stacked word lines, respectively, thereby selectively operating desired memory cells.
However, in order to realize the above-mentioned structure, contact plugs having various depths should be formed, and thus, difficulty of a process is high. Also, since the contact plug passes through the word line, there is a possibility of causing a bridge.